demo_maintenance_project_plan.xml

<odoo noupdate="1">
        <record id="maintenance_plan_monthly_equipment2_task" model="maintenance.plan">
            <field name="equipment_id" ref="maintenance_project.equipment_2" />
            <field
            name="maintenance_kind_id"
            ref="maintenance_plan.maintenance_kind_monthly"
        />
            <field name="project_id" ref="maintenance_project.project_project_1" />
            <field name="task_id" ref="maintenance_project.project_task_12" />
            <field name="interval">30</field>
            <field name="interval_step">day</field>
            <field name="duration">2</field>
        </record>
        <record
        id="maintenance_plan_monthly_equipment2_notask"
        model="maintenance.plan"
    >
            <field name="equipment_id" ref="maintenance_project.equipment_2" />
            <field
            name="maintenance_kind_id"
            ref="maintenance_plan.maintenance_kind_weekly"
        />
            <field name="project_id" ref="maintenance_project.project_project_1" />
            <field name="interval">7</field>
            <field name="interval_step">day</field>
            <field name="duration">1</field>
        </record>
</odoo>